1. FIELD OF THE INVENTION
The present invention relates to air-to-fuel ratio control systems, and more particularly the invention relates to a control system for electrically controlling the air-to-fuel ratio of the mixture produced in the carburetor of an internal combustion engine for automobiles.
2. DESCRIPTION OF THE PRIOR ART
Conventional internal combustion engines for automobiles have been so constructed that the weight ratio between the amount of intake air and the amount of fuel to be mixed, i.e. the air-to-fuel ratio of the mixture produced in the carburetor is controlled in accordance with a few engine operating conditions such as the throttle opening and the amount of intake air. However, with a recent tendency toward cleaner exhaust emissions, the demand for reduction in fuel consumption necessitated by a recent steep rise in the price of gasoline, etc., increasingly complicated air-to-fuel ratio controlling characteristics are required for the carburetors, and moreover there also exists a need for highly accurate air-to-fuel ratio control.
On the other hand, the driver of an automobile carrying an internal combustion engine requires, as the essential requisites for the driving of his vehicle, that the driver can drive his vehicle at any desired speed, and that improved driveability in terms of acceleration performance, etc., is ensured. In view of the fact that the vehicle speed has an important bearing on the needs of the society, i.e., cleaner exhaust emissions and reduced fuel consumption, it should be appreciated that the speed of the automotive vehicle among vehicle driving conditions is an important control parameter for the internal combustion engine mounted on the vehicle. However, none of prior art systems have regarded it as important.